Controller.



PATBN'IED NOV. 12, 1907-.

L. L.,'I"ATUM. CONTROLLER. APPLIOATIO! FILED APR-16, 1906.

2 SHEETS-SHEET 1.

WITNESSES ML TRY INL No. 870,595- PA'IENTED NOV. 12. 1907. L. L. TATUM.

CONTROLLER.

Arrmoulol rnnn' um. 10. nos.

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Fig.1

'W 11% WW WITNESSES Lewis L.Talum ATTORNEY UNITED sTA qps iirrENT OFFICE.

LEWIS L. TATUM, OF NORWOOD OHIO ASSIGNOR TO ALLIS-CHALMERS COMPANY, A CORPO- RATION OF NEW JERSEY, AND THE BULLOCK ELECTRIC MANUFACTURING COMPANY, A

CORPORATION OF OHIO.

CONTROLLER.

Specification of Letters Patent.

Patented Nov. 12, 1907.

Application filed April 16, 1906. Serial No. 311,843.

T 0 all whom it may concern:

Be it known that 1. LEWIS L. TATUM. a citizen of the United States. residing at Norwood. in the county of Hamilton and State of Ohio. have invented certain new and useful Improvements in Controllers of which the following is a full. clear. and exact specification.

My invention relates to controllers for electric motors. and particularly to controllers for starting and regulating polyphase induction motors.

The object of my invention is to provide a simple.

compact and. inexpensive controller for use with heavy i currents or high voltages. which shall be capable of l sure operation with greatly reduced labor.

Heretofore controllers for heavy currents have either had large sliding contacts under great spring pressure. in which case the labor of operating the controller was excessive. or else have used separate solenoid switches under the control of a master controller, in which case there were losses of energy in the solenoids and great 1 i and a pair of cams on said shaft for each group of complications in the system of wiring.

With my invention the great labor in operation. the energy loss in solenoids. and the complicated wiring of the controlling circuits are all avoided and the contacts of the controller are positively closed with a firm contact. and positively and widely opened with a quick break. thereby being able to carry heavy currents safely and at the same time prevent ing dangerous arcing.

My invention is especially applicable to mill inot'ors and mine hoists where it is necessary to frequently start, stop and reverse the motors. it is also well adapted for use on electric locomotives. and in all places when large currents or high voltages are to be controlled The current carrying parts may be large as desired and are POSltlVGlY and quickly operated both in opening and closing. the greatest pressure being applied in closing at the time when the contacts engage so that a firm contact is insured. The operating mechanism may be of small radius but the switches controlled thereby may be arranged on a much larger radius. And in addition the controller is simple in operation and construction. compact in form. and inexpensive to manufacture.

In one aspect. my invention comprises a shaft carrying cams. and a plurality of snap switches arranged to be operated by said cams as the shaft is rotated.

In a more specific aspect. my invention comprises a. rotatable shaft, a plurality of cams on the shaft. and a plurality of similar groups of snap switches. the corresponding switches of the groups being simultaneously closed and the different switches of each group successively closed by certain of the cams-as the shaft. is

rotated in one direction. and the corresponding switches 1 5 others of the cams as the shaft is rotated in the other direction.

From another point of view my invention consists of the combination of a rotatable shaft. with a plurality of cams on said shaft. and a plurality of snap switches arranged to be closed by some of said cams and opened by others of said cams as the shaft is rotated.

In another aspect my invention consists of an induction motororesistance in the rotor circuit of the motor, a plurality of snap switches each arranged to short-circuit a portion of said resistance, a rotatable shaft, a pair of cams on said shaft, so arranged that one of said cams closes said switches successively as the shaft is ro ated in one direction and the other cam opens said switches as the shaft is rotated in the other direction.

Still more specifically my invention comprises a three-phase induction motor, a Y-connected resistance in its rotor circuit. a group of snap switches associated with each section of said resistance, a rotatable shaft,

switches, one of each pair of cams being arranged to close its associated switches successively as the shaft is rotated in one direction, the other of each pair of cams being arranged to open said switches successively as the shaft. is rotated in the other direction. corresponding switches of the various groups being operated simultaneously.

Figure 1 is an elevation of my controller with half of the casing removed. Fig. 2 is a section on the line 2-2 of Fig. l. Fig. 3 is a section on the line 33 of Fig. 1. Fig. 4 is a modification showing a spring actuated toggle switch. Fig. 5 is another modification showing a latched spring opened snap switch. Fig. (5 is a section on the line 6-tl of Fig. 5. showing a detail of the trip lever and lower cam in Fig. 5. and Fig. 7 is a diagram of connections showing my invention applied to a three-phase induction motor.

in the drawings A is a controller casing in which is journaled a shaft B operated by the usual handle B". Fixed to the shaft as by pins 1). are cams C. C D, D and E. E arranged in pairs. If desired. the cams may be provided with anti-friction rollers at. their ends. The cams C. D and E are arranged vertically in line. the cams t"-, D and 15" being arranged in another vertical line. These two lines of cams are angularly displaced from each other. as shown in Figs. 2 and 3.

Mounted on the casing are groups of snap switches F. F. F, F; G. G G G and H H H H, the switches of each group. as F, F. F and F, being horizontally in line, and the corresponding switch of the different. groups. as F. G and H. being vertically in line. Each oi these snap switches is arranged to be operated b; a toggle I, the toggles in turn being operated by the cams 0- etc. As the are shown open in Fig. 1. Whenthe switches are closed the arms I, I are moved a little beyond alinement, sothat the switches will be locked closed, too' great movement in this direction being prevented by fingers t on arms I. In closing the switch, the

first part of the movement is against no pressure, and

the toggle then needs and has but a comparatively small mechanical advantage, but when the switch contacts engage, the toggle arms are nearly in line, and the mechanical advantage of the cams in forcing the contacts firmly together is, very great. This gives a good eo'ntact and saves labor on the part of the. operator. In opening the switches gravity may be assisted by springs I as shown in Fig. 4, or, if the controller toggles are placed horizontally or the controller inverted, the

springs act alone.

When the shaft is in off position, t. e. when it has been moved as far as it will go in an anti-'clock I wise direction, all of the snap switches are open. As

the shaft is rotated in a clockwise direction the opening cams C D and E swing freely past the lower ends of arms I, doing nothing, but the closing cams V G, D and E which are but a small angular distance behind the opening cams, engage the upper ends of arms I closing the corresponding-switches of the various groups, as F, G and H, simultaneously and the different switches of'the same group as F, F, F and F, successively. As the shaft is rotated in an anti-clockwise direction, the reverse action takes place, the closing cams first passing the arms I, doing nothing, and tlieopening cams following and engaging the lowerparts of the arms I, to simultaneously trip corresponding switches of the various groups and successively trip the different switches of the'same group. When either the opening or the closing cams operate the switches, the other set of cams is entirely out of the way, so as not to interfere with the free action of the switches.

In Figs. 5 and 6 is shown a modification of the snap switch of my controller. Oniho shaft B, are mounted the cams C and C the cam (3, being similar to the cams 0 above described and acting to close the snap switch F directly instead of through a. toggle I, l. The switch F is held closed by a latch M, pressed upwardly- .bya leaf spring N. The upper surface'of latch M, is founded, as shown in Fig. 6, thelower surface of cam C, being correspondingly rounded or beveled, so that as the shaft B is rotated and the cam C engages latch M, the latter is pressed downwardly against spring N and the switch F tripped, thus allowingit to be opened by the compression spring '0.

It would not always be necessary to arrange the snap switches in groups, corresponding switches of the groups beiug operated simultaneously, but all of the switrhes could be arranged tobe operated successively if it were so desired. I have shown and described my controller with groups of switches, however, because, the controller is primarily intended to be used for starting and regulating induction motors, and especially three-phase induction motors. In Fig. 7 is shown diagrammatically my controller applied-to a three-phase induction motor. The supply mains are represented by 1, 2 and 3, the stator windings by 4, 5 and 6, and the rotor by 7;- The stator windings are here shown delta connected but it is obvious that other methods of connecting could used. Leading from the slip rings of the .rotor are wires-8, '9 and 10, which lead to'resistance sections "11,- 12 and-l3. The resistances may b' connected in any desired manner but are. here shown Y-connec'ted, to correspond with the rotor winding. The method of connecting the resistance depends on the method of connecting the rotor windings, the two generally corresponding. Each section of resistance is associatedwith a group of the switches of the controller, and each switch is arrangedEecut-out a part of its resistance s'ection. When it is es'ired to start the motor, the controllerbeing in off or high resistance positiorntlie hand' i switch K is closed. The rotor circuit now has all the resistance I1, 12 and 13 in circuit. When'the motor has gained sufiicient speed, the controller is moved to simultaneously close the corresponding switches F, G and H to cut out parts of the resistance sections.-

'As the motor .gain's greater and greater speed, the 'con'' troll'er-is moved'to cut out'more and more resistance until finally, by closing'switches'F, G-and H, all ,the resistance is cut out., When theg'controller is moved in the other direction the'snap switches are opened to cut in the'resistaiice again and the opening of switch K stops-the motor. Itis not absolutely necessary to close corresponding switches of the vari-' ous groups simultaneously, but it is better to do soin order to keep the system balanced.

If desired instead of'havingi just one opening cam for each group of switches, there may be two such sider.to-be its preferred form, but it is'not limited to the precise .structure shown and described. It is obvious that many equivalents may be substituted 1 have described my invention in whatI new (on-- for the various parts shown and described without.

departing from the spirit of my inventionfand I claim all such obvious.modifications'as falling thereunder.

What'I claim as'new and desire to secure by Letters Patent is:-

1. In-a controller, a rotatable shaft. a plurality of crime 4. In a controller, a. rotatable shaft, cams on said shaft,

and a plurality of toggle switches arranged to be operated each of said cams as the shaft is rotated.

5. In a controller, a rotatable shaft, :r'plurality of cams on said shaft, and a plurality of snap switches, each cam being arranged to operate a number of said switches successively as the shaft is rotated.

6. In a controller, a rotatable shaft, a plurality of cams on said shaft and a plurality of snap switches arranged to be closed successively by some of said cams and opened successively by others of said cums as the shaft is rotated,

each cam operating more than one of said switches.

7. In a controller, a rotatable shaft, a plurality of cams on said shaft, and a. plurality of snap switches arranged to be simultaneously closed by some of said cams and simultaneously opened by others of said cams as the shaft is rotated in one direction or the other.

8. In a controller, a rotatable shaft, :1 pair of cams on. said shaft, and a plurality-of switches arranged to be close-(l by one of said cams and opened by the other of said cams as the shaft is rotated.

9. In a controller, a rotatable shaft, :1 pair of cams on said shaft, and a plurality of snap switches arranged to bev successively closed by one of said cams as the shaft is 1'0- tated in one direction and to be successively opened by the other cam as the shaft is rotated in the other direction.

10. In a controller, a rotatable shaft, a pair of'cams on said shaft, and a plurality of toggle switches arranged to be closed by one of said cams and opened by the other.

11. In a controller, a rotatable shaft, cams on said shaft, and a plurality of switches arranged to be operated by one of said cams as the shaft is rotated in one direction, and by another of said cams as the shaft is rotated in the other direction. Y

12. In a controller, a rotatable shaft, a pair of cams on said shaft, a switch, and means. normally in ,the path of one of said cams and arranged to be moved by said cam into the path of the other cam as the shaft is rotated in one direction, and to he moved by said othencam into the path of ihetirst as the shaft is rotated in the other direction. said means operating the switch as it is moved. 13. In a controller, a rotatable shaft, a plurality of cums on said shaft, and a plurality of groups of snap switches. the different switches of a group being arranged to be successively operated by said cams as the shaft is rotated,

14. In a controller. a shaft, a plurality of cams on said shaft, and u plurality of groups of snap switches, the different switches of a group being arranged to be successively closed by some of the cams as the shaft is'rotated in one direction and successively opened by other cams as the shaft is rotated in the other direction.

15. in a controller", a shaft, :1 plurality of cams on said shaft, and a plurality of similar groups of snap switches, corrcsponding switches of the groups being arranged to be simultarcously operated by the cams as the shaft is ro tatcd.

iii. In a controller, a shaft, a plurality of cams on said shaft. and a plurality of similar groups of snap switches, the c r be multaneously closed by some of the cams as the shaft is rotated in one direction, and simultaneously opened by rs of the cams as the shaft is rotated in the other tion.

. in a controller. a shaft, a plurality of cams on said the corresponding switches of the grthips being sinlultanm nusly operated and the different switches of each group being successively operated by the cams as the shaft is rorated IS, in a controller, a shaft, aplurality of cams on said shaft, and a plurality of similar groups of snap switches, the corresponding switches of the groups beingsimultaneously closed and the different switches of each group sucthe groups being simultaneously opened and the diii'crcnt switches of each group successively opened by others of the cams as the shaft is rotated in the other direction.

19. in a controller, a rotatable shaft, a plurality of groups of snap switches, and a pair of cams on the shaft t and a plurality of similar groups of snap switches,

responding switches of the groups being arranged to for each group of switches, 'one of each pair of cams being arranged to close its group ofswitches as the shaft is r0- tated in one direction, the other'of each pair of cams being arranged to open its group 'of switches as the shaft is rotated in the other direction.

20. In a controller, a rotatable shaft, a plurality of groups of snap switches, and a cam on the shaft foreach group of switches, each of said cams being arranged to op crate its group of switches as the shaft is rotated.

operate the diiferent switches of its group successively as.

the shaft is rotated.

23. In a controller for induction motors, a shaft, :1

group of switches for each current phase of'the motot, and

a cam on the shaft for each group ofswltchgg arranged to simuitanepusiy as the shaft isj r'otatadx operate the corresponding swltchespf the diflerent groups" p 241 In a controller for. induction motors, a shaftfa.

group .of switches for each 1 rrent phase of the motor, and a pair of cams on the shaft fo'r each group of switches so arranged that oneof each pair of cams closes its switches successively as the shaft is rotated in one direction and the other of each pairopens its switchessuccessively as the shaft is rotated in the other direction. 7

' 25. In combination, an induction motor, a resistance in the rotor circuit of said motor, a plurality of snap switches, each arranged to short circuit a portion of said resistance, a rotatable shaft, and a cam on said shaft arranged to operate said switches as the shaft is rotated.

26. In combination, an induction motor, a resistance in the rotor circuit thereof, a plurality of snap switches, each arranged to shortcircuit a portion of said resistance, a ro.- tatable shaft, and a pair of cams on said shaft, so arranged that one of said cams closes said switches successively as the shaft is rotated in one direction and the other cam opens said switches as the shaft vis rotated in the other direction.

group of snap switches associated with the resistancefor each phase, each switch being arranged to short-circuit a portion of its associated resistance, a rotatable shaft, and

-7. In combination, a polyphase induction motor, a re sistance for each phase of the rotor circuit of the motor, a

each phase, each switch being arranged to short-circuit a portion of its associated resistance, a rotatable shaft, and

a cam on the shaft for each group of switches arranged jo operate corresponding switches of the various groups si mullancously as the shaft is rotated.

20. In combination, a polyphase induction motor, a rc sistailcc for each phase of'lhe rotor circuit of the motor, a

group of snap switches associated with the resistance for' each phase, each switch being arranged to shortcjrcuit a portion of. its associated resistance, a rotatable shaft, and :1 rain on the shaft for each group of switches arranged to operate corresponding switches of the various groups siuiultoueously and the different switches of each group successively as the shaft is rotated.

30. In combination, a polyphase induction motor, a re sistauce for each phase of the rotor circuit of the motor, a

; group of snap switches associated with the resistance for ccssivciy closed by certain of thecams as the shaft is ro 5 rated in one direction, and the corresponding switches of each phase, each switch being arranged to sl\ortcircuit a portion of its associated resistance, a rotatable shaft, and

a pair of cams on the shaft for each group of switches, one

31. In combination, a poiyphase induction motor, a resistance for each phase of the rotor circuit of the motor,

group of snap switches associated with the resistance of each phase, each switch being arranged to short-circuit a portion of its associated; resistance, a rotatable shaft, and

a pair of cams on theshaft for each group of switches, one of each pair of cams closing the corresponding switches of thevarious groups simultaneotisiy as the shaftjs rotated in one direction and the other of each pair of cams openin: said' corresponding switches simultaneously as the shaft is rotated in the other direction.

32. in combination, a three-phase induction motor, a Y-connected resistance in its rotor circuit, a group of snap switches associated with each section ofsaid resistance,

and means for operating the different switches of'each group successively to gradually cut out said resistance.

33. In combination, a three-phase induction motor, a'

Y-connected resistance in its rotor circuit, a group of snap switches associated with each section of said resistance,

and means for operating' the corresponding switches of the various groups simultaneously to cut out parts of their associated resistance sections.

$4.1m combination, a three-phaseinduction motor, a Y-connected resistance in its rotor circuit, a group of snap switches associated with each section of said resistance, a rotatable shaft, and cams on said shaftfor opening or closing said switches according to the direction of rotation of said shaft.

35. In combination, a three-phaseinduction motor,

Y-connected resistance in its rotor circuit, a group of snap switches associated with each section of said resistance, a

rotatable shaft and a pair of cams on said shaft for each group of switches for closing corresponding switches of the various groups simultaneously as the shaft is rotated in one direction and opening said corresponding switches simultaneously as the shaft is rotated in the other direction.

36. In combination, a three-phase induction motor, a

Y-connected resistance in its rotor circuit, a group of snap switches associated with each section of said resistance,

group of switches, one of each pair of cams being arranged to close its associated switchesas the'shaft is rotated in one direction, the other of each pair of cams being arrotated in one direction the other of each pair of cams being arranged to open said switches successively as the shaft is rotated in the otherdirection, corresponding switches of the ,various groups being operated simuitane onsly. In testimony whereof I aflix my signature, in the presence of twof'witness'es.

" LEWIS L. TATUM.

Witnesses:

GEO. B. SCHLEY, FRED .i'. Kmsny.

40 rotatable shaft, and a pair of cams on "said shaft for each 

